#include<bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 131072;
multiset<int> t[2 * N];
const int inf = 1e9;
void add(int l, int r, int val, int ind = 1, int L = 0, int R = N - 1) {
if (l <= L && R <= r) {
t[ind].insert(val);
return;
}
if (r < L || l > R) return;
int M = (L + R) / 2;
add(l, r, val, 2 * ind, L, M);
add(l, r, val, 2 * ind + 1, M + 1, R);
}
void rem(int l, int r, int val, int ind = 1, int L = 0, int R = N - 1) {
if (l <= L && R <= r) {
t[ind].erase(t[ind].find(val));
return;
}
if (r < L || l > R) return;
int M = (L + R) / 2;
rem(l, r, val, 2 * ind, L, M);
rem(l, r, val, 2 * ind + 1, M + 1, R);
}
int getmin(int x, int ind = 1, int L = 0, int R = N - 1) {
if (x < L || x > R) return inf;
int res = (t[ind].size() ? *t[ind].begin() : inf);
if (L == R) return res;
int M = (L + R) / 2;
res = min(res, getmin(x, 2 * ind, L, M));
res = min(res, getmin(x, 2 * ind + 1, M + 1, R));
return res;
}
const int M = 100000;
const int S = 200010;
vector<pair<int, int>> a[M];
vector<int> xs[M];
map<int, int> id[M];
vector<int> day;
vector<pair<int, ll>> g[S];
ll dt[S];
int par[S];
int n;
void dfs(int x) {
for (auto [y, w]: g[x]) {
assert(day[y] == day[x] || day[y] == day[x] - 1);
par[y] = x;
dfs(y);
if (day[y] != day[x]) {
if (w < dt[x]) {
dt[x] = w;
}
} else {
if (w + dt[y] < dt[x]) {
dt[x] = w + dt[y];
}
}
}
sort(g[x].begin(), g[x].end(), [&](const pair<int, ll> & y, const pair<int, ll> & z) {
ll vy = day[y.first] != day[x] ? y.second : y.second + dt[y.first];
ll vz = day[z.first] != day[x] ? z.second : z.second + dt[z.first];
return vy < vz;
});
}
vector<pair<int, int>> qu[M + 1];
int vis[M + 1];
int ci;
vector<ll> path;
vector<ll> ans;
int mx[S + 1], dep1[S + 1];
int dfs2(int x) {
if (x != ci - 1 && day[par[x]] != day[x]) {
int bad = getmin(day[x]);
for (auto [i, qi]: qu[day[x]]) {
if (i > bad) break;
ans[qi] = min(ans[qi], path.back() - path[n - i]);
}
}
mx[x] = day[x];
dep1[x] = -1;
for (auto [y, w]: g[x]) {
if (day[y] == day[x]) path.back() += w;
else path.push_back(path.back() + w);
int dep = dfs2(y);
if (y == g[x][0].first) {
dep1[x] = dep;
add(dep, day[x], day[x]);
}
mx[x] = min(mx[x], dep);
if (day[y] == day[x]) path.back() -= w;
else path.pop_back();
}
if (dep1[x] != -1) {
rem(dep1[x], day[x], day[x]);
}
return mx[x];
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
ll t;
cin >> n >> t;
for (int i = 0; i < n - 1; ++i) {
int m;
cin >> m;
a[i].resize(m);
for (auto & [x, y]: a[i]) {
cin >> x >> y;
}
sort(a[i].begin(), a[i].end());
vector<pair<int, int>> b;
for (auto [x, y]: a[i]) {
if (b.size() && b.back().first == x) continue;
while (b.size() && b.back().second >= y) b.pop_back();
b.emplace_back(x, y);
}
a[i] = b;
for (auto [x, y]: a[i]) {
xs[i].push_back(x);
xs[i + 1].push_back(y);
}
}
ci = 0;
for (int i = 0; i < n; ++i) {
sort(xs[i].begin(), xs[i].end());
xs[i].erase(unique(xs[i].begin(), xs[i].end()), xs[i].end());
for (auto x: xs[i]) {
day.push_back(i);
id[i][x] = ci++;
}
}
vector<set<int>> ex(n);
for (int i = 0; i < n - 1; ++i) {
for (auto [x, y]: a[i]) {
ex[i].insert(x);
}
}
day.push_back(n);
ci++;
for (int i = 0; i < n - 1; ++i) {
for (int j = 0; j < a[i].size(); ++j) {
int tx = a[i][j].first, ty = a[i][j].second;
int x = id[i][tx], y = id[i + 1][ty];
g[y].push_back({x, ty - tx});
if (i == n - 2) {
g[ci - 1].push_back({y, 0});
} else {
auto it = ex[i + 1].lower_bound(ty);
if (it == ex[i + 1].end()) {
int nt = *(ex[i + 1].begin());
int tt = nt + t - ty;
g[id[i + 1][nt]].push_back({y, tt});
} else if ((*it) != ty) {
g[id[i + 1][*it]].push_back({y, (*it) - ty});
}
}
}
}
const ll inf = 1e18;
for (int i = 0; i < ci; ++i) {
dt[i] = inf;
par[i] = -1;
}
dfs(ci - 1);
int q;
cin >> q;
map<pair<int, int>, int> has;
ans = vector<ll>(q, inf);
for (int i = 0; i < q; ++i) {
int x, y;
cin >> x >> y;
x--; y--;
if (has.find({x, y}) != has.end()) {
ans[i] = -1 - has[{x, y}];
} else {
has[{x, y}] = i;
qu[x].push_back({y, i});
}
}
for (int i = 0; i <= n; ++i) {
sort(qu[i].begin(), qu[i].end());
}
path.push_back(0LL);
dfs2(ci - 1);
for (auto & x: ans) {
if (x < 0) x = ans[-(x + 1)];
cout << x << "\n";
}
}
